[morzh]

Your 6.3V supplies 0.3+0.3+0.7+0.25=1.55A
Your 5V supplies 2A

I do not know exactly how much the 630V supplies, (well it is centertap so it is 1/2 that rectified) but since the heater power is known, 20W (from above) and the total power is 43W so the 630V supplies about 23W then (43-20 ) which makes it 39mA but then each half conducts 1/2 time so it is 73mA.

So, give it some margin, like 20% maybe...

So, 6.3V/2A, 5V/2.5A, 630V/0.09A


PS. After looking at the org specs I can see they did not use margin, and rated the windings exactly with what I calculated.
6.3/1.5A, 5/2A and the 630V is at 55mA meaning they count on not drawing maximum power continuously.